Citigroup Inc.’s trading revenue is on pace to drop 15 percent in the third quarter from a year earlier as volatility remains “somewhat subdued,” Chief Financial Officer John Gerspach said.

Last year’s performance benefited from a boost in activity as clients wagered on prospects for the U.S. election, while this quarter has seen no comparable catalyst, Gerspach told investors Monday at a conference hosted by Barclays Plc in New York. The last three weeks of this month could swing the quarterly results, he said.

The biggest investment banks posted declines in trading revenue in the second quarter as volatility dropped and as asset managers waited to see if central banks would raise interest rates and Donald Trump’s administration could enact any of its policy goals. The calm markets helped many banks’ other businesses, including wealth management.

Citigroup reported $4.07 billion of trading revenue in the third quarter of last year, according to the company’s earnings supplement. A 15 percent drop would mean revenue of $3.46 billion, which would be the lowest quarterly figure since the final three months of 2015.

“For the whole third quarter you really don’t know what happens until you figure out what the operating environment is in September,” Gerspach said.

Citigroup also said that 2017 net credit-card losses would be worse than previously expected. Gerspach said the rate in the branded-cards business would climb to 285 basis points from an earlier estimate of 280 basis points. In the retail-services business, which includes store cards, the figure will increase to 470 basis points from an earlier expectation of 460 basis points, Gerspach said.

“Very, very small increases in the NCL rates, but obviously even small increases in the NCL rate do have an impact on our reserving actions,” Gerspach said.